The vernacular explains intranet, extranet, broadband, bandwidth, traffic, and internet speed

From the public account: Pentale Programmer Author: BossXiang

One. What is the difference between bandwidth and broadband?

Bandwidth is

量词

, refers to:

网速的大小

, for example, 1Mbps means

一兆比特每秒

, this value refers to:

带宽

。

Broadband is

名词

illustrate

网络的传输速率速很高 。

Broadband

标准各不相同，最初认为128kbps以上带宽的就是宽带

, and the following is the narrow band.

But now domestic carriers generally offer it

至少512kbps带宽的宽带服务。

Other words

带宽

is one

具体数值

whereas

宽带

It is the one that satisfies a certain bandwidth value

传输标准(服务)。

That is, broadband is a kind of service, and bandwidth is the transmission speed.

Broadband: Commonly referred to in digital communications 64kbit/s The bandwidth of the above signal.
Narrowband: Commonly referred to in digital communications 64kbit/s The bandwidth of the following signals.

1. Broadband

Usually people will say that your home can access the Internet? Actually, that's what it means

你家有没有宽带，

In other words, it's a noun,

先有了宽带一词，然后才可以说你带宽是多少，

Broadband is not directly related to the speed at which you can access the Internet.

2. Bandwidth

When we want to apply for broadband, we need to register with some service providers, and this will be the case

套餐

The difference you may have

10Mb/s 、 20Mb/s

You can calculate your own bandwidth by computer byte conversion ratio

Like what:

1B=8b //1字节=8位              1KB=1024B              1MB=1024KB              1GB=1024MB

The bandwidth we applied for was:

10Mb/s

The b in this unit is lowercase, and the 1B (bytes) = 8b (bits) we just said here is exactly 8 times the relationship, that is, the download speed:

10Mb / 8 = 1.25MB

Some people will ask, why divide by 8?

In the computer,

下载速度是

in order to

字节(B)

for the unit, while

提供商

That's right

比特(b)

for units.

For example: download a piece of software on the Internet, and it will be: B(字节) For example, if you open a web page, there may be pictures, text, videos and other content in this web page, which are essentially downloaded to your computer and then you can see them.

We can calculate our own download speed with bandwidth:

Calculation:

带宽大小 / 8

bandwidth	Download speed	formula
The bandwidth is 2Mb	The download speed is 256KB/s	2 / 8 = 0.25
The bandwidth is 4Mb	The download speed is 512KB/s	4 / 8 = 0.5
The bandwidth is 8Mb	The download speed is 1.00MB/s	8 / 8= 1.0
The bandwidth is 10Mb	The download speed is 1.25MB/s	10 / 8 = 1.25
The bandwidth is 20Mb	The download speed is 2.50MB/s	20 / 8 = 2.50
The bandwidth is 100Mb	The download speed is 12.5MB/s	100 / 8 = 12.50

Sometimes, when using some software to test the Internet speed, we find that there is a bit of a gap with the results we calculated, which is normal, this is due to some 物理线路磨损
and other objective reasons. Sometimes, when you download software in the middle of the night, you will find that the download speed exceeds the value we have calculated theoretically, and this situation also exists

We can understand it like this: For example, if your home is in Zone J, then the bus line from the provider to Zone J is 100Mb/s, and your home is 10M, because the restrictions are set from the router, this is related to the settings of the router.

The second situation is that the server where you download the software is relatively idle, so the speed is also relatively fast

The third situation is that when we download the software, we may use the software in this area, because there are more people who download this software, then his speed is also relatively fast.

In layman's terms:

Bandwidth is like yours

水龙头大小

, the speed of the Internet is comparable

从水龙头里出来的水流速有多快。

All of the above is talking about download speed, then

上传速度是怎么计算的呢，其实上传速度这个与地域的不同而不同，一般上传速度都被提供商限制了，

I can't say for sure.

3. Traffic

The flow is:

对外发送数据与接收数据包的大小总和，

Units are taken

1024进制

of, the unit has

B,KB,MB(M),GB(G)

1G=1024MB              1M=1024KB              1KB=1024字节(B）

Generally we have it on our mobile phones 5元30MB,10元70MB
When we open a web page, how much traffic do we need? (formerly Ha)

Let's say there is a web page
100个汉字与一张100KB的图片 ， 一个汉字=2个字节 That is, the data size of this page is: 100 * 2B / 1024 + 100KB = 0.2KB +100KB =100.2KB； Each time you visit this page, you will be generated 100.2KB of traffic, if it is 70MB , then the number of web pages visited is basically gone, so let alone watching videos.

Two. The relationship between bandwidth, speed, and traffic

Usually: we say

我家的带宽10M              现在网速网速：200KB/s              看一张图片使用了8M的流量

So what is the relationship between bandwidth, network speed, and traffic, and what do they represent?

1. The bandwidth unit is:

比特/秒（bps）：10M=10Mbps

2. Internet speed is

数据传输的速度

in the following units:

字节/秒 (B/s， KB/s， MB/s)

1MB/s=1024KB/s              1KB/s=1024B/s

3. The traffic is the user's access to the Internet

发送和接收

target

数据量总和

in the following units:

字节（Byte）

；

A bit is the smallest unit of information: 1字节=8比特 That is, 1B=8bit or 1B=8b 1字节/秒=8比特/秒 (1B/s=8bps) 1比特 (1b or 1位) is the smallest unit of storage in information technology, 1位代表一个“1”或者“0”
；

1B (1 byte) is a relatively small storage unit: under normal circumstances, 1 English letter occupies 1 byte; A Chinese character occupies 2 bytes;

4. Conversion between them: bandwidth size / 8

10M带宽(10Mb/s)=1.25MB/s网速              1M带宽(1Mb/s)=0.125MB/s=128KB/s              10Mbps = 10*1024Kbps =10*1024*1024bps =10*1024*1024/8 Byte/s =10/8 MB/s =1.25 MB/s

Three. What do upstream bandwidth and downstream bandwidth mean? What does each do?

What do you mean by upstream bandwidth and downstream bandwidth, or upstream speed and downstream speed?

When setting the speed limit of the router, or configuring some other software, you will encounter the configuration of the uplink speed and downlink speed, many users do not know what these two mean, and the following will explain these two in detail:

There are two behaviors when accessing the internet:

一是上传数据，二是下载数据。

Uplink broadband (speed) refers to:

上传的速度

, while downlink broadband (speed) refers to

下载数据时的数度。

In detail, it can be understood as:

The uplink bandwidth is the uplink rate

Generally, yes

指从你的电脑上传的速度

, the rate at which someone else is communicating with your computer. For example, if you upload your photos to QQ space, the speed of uploading photos at this time is the uplink speed, and when you upload files to some cloud disks, the speed at this time is also the uplink rate, and we may find that under normal circumstances, the speed of uploading files is much slower than the network speed we usually use.

Downlink bandwidth is the downlink rate

Generally, yes

你从网络上的主机下载的速度，

For example, the speed at which you download a file, the speed at which you open a web page, this speed is the downlink rate.

下行速率通常就是我们平常所说的网速，

For example, if your bandwidth is 8M for telecom and 20M for optical fiber, this speed actually refers to the downlink rate of the network.

Uplink broadband (speed) and downlink broadband (speed) are

不对称的。

Generally, yes

下行速度大于上行的速度。

We usually use it

宽带说多少M

, all refer to

下行宽带，因为我们上网主要是从互联网上下载数据，而上传的数据量要少很多。

Why is it that in the process of using broadband, I find that the download speed of the computer cannot meet the standard of my own broadband, such as 10Mb/s broadband, and the download speed is only about 1MB/s, why is this?

Because the downlink speed of the bandwidth of a broadband operator is different from the downlink speed of a Windows computer, the unit of a Windows computer is

KBbs/s,

And the unit on the broadband operation is:

Kbbs/s

, 1B = 8b (1 byte = 8 bits).

Suppose you handle 10M broadband, 10Mbps=10240Kbps/8=1280KBps , so the maximum download speed on your computer is only 1280KBps , which is about 1.25MB/s. So don't say that the broadband company cheats people and handles the broadband deduction, which is just caused by the different units of calculation.

Broadband

下载速率

In addition to the broadband bandwidth, it is related to the computer configuration, the download software used, the size of the download, the speed of the download website, etc., and the broadband download rate (such as Xunlei) that can be viewed by the general download software.

Ideally, the downlink broadband of 100M fiber broadband is in 10M/S-11M/s Between; Uplink broadband refers to the speed at which you upload to the internet; 这个要开你开通的宽带是上下行等同还是不等同了
； If you don't know, you can consult your operator; If it is equivalent, your uplink broadband is also between 10M/s and 11M/s; It is not equivalent, and the general uplink broadband is only 400 kbs/s to 500 Kbs/s.

Concentrate:
一般企业开通的是上下行带宽等同的；家用的是不等同，一般只管下行带宽，上行的不管的。

Four. Upstream and downstream bandwidth understanding of the server

For servers,

客户端下载资源

What is consumed is the upstream traffic of the server,

客户端上传资源

What is consumed is the downstream traffic of the server,

Servers that are usually bought, such as Alibaba Cloud, generally refer to the bandwidth they buy

上行带宽，下行通常是不限的。

And

流量的计算一般都是以上行的来计算的。

客户端上传资源，对服务器的带宽基本没有影响

Because

服务器的下行基本不限的，

It has an impact on the bandwidth of the client's own network;

whereas

客户端下载资源，

In addition to the bandwidth of the server, it also has an impact on the network bandwidth of the client itself.

The upstream bandwidth of the server

The upstream bandwidth of the server is mainly used for:

本地用户请求服务器上的资源(每秒钟服务器传给客户端的最大数据量,服务器流出的带宽

(i.e., local download, server upload)', if you download files on the server on other machines, the main uplink bandwidth of the server is used.

Here we must distinguish between the upstream bandwidth and the downstream bandwidth, and the download speed of the personal PC depends on the downstream bandwidth of the server and the upstream bandwidth of the server

The personal PC (A) is connected to the server (B), and the maximum uplink bandwidth (uplink speed) of server B determines the maximum download speed of the PC.

The downstream bandwidth of the server

Downstream bandwidth

主要用于本地用户上传文件至服务器(客户上传数据到服务器)

For the server, the downlink bandwidth is unlimited, and the network factor depends on the client's current network situation

Five. Differences between internal IP addresses and public IP addresses

distinguish

As shown in the figure, suppose our computer is device one and wants to access Baidu.

If used 校园网 , first of all, you need to pass first 校园网的路由器 Take ours 内网ip Turn to 校园网的 外网ip。 And then through this 外网ip Connect it first 湖南电信的网关， Finally on the connection 百度的网关。 百度 Put you 请求的信息回传 to yours 校园网网关 ， 校园网网关 Then put the information 传给你 (The entire network presents.) 网状结构 , which will automatically find a path to Baidu - 基于深度优先搜索或者广度优先搜索 ）。

This process is similar to Taobao shopping.

Suppose a book is ordered at school, 淘宝 Received yours over there 订单
Prepare your items and start shipping them.

He found yours
收货地址在湖南， So it could come from 杭州出发 , went first 福建的中转站， And then again 江西的中转站 , suddenly discovered 江西到湖南的中转站不通， So it can only go around to the transit station in Guangdong, and finally 再到湖南中转站。 这些中转站就相当于公网上的各个网关。 It's here 湖南中转站 , the courier brother will deliver the package to you 校门
(This is the last level of gateway).

At this time, the courier brother left,
校门 place 管理人员 In the basis of yours 宿舍信息 I'll give you the package. (The exchange of information within the LAN is carried out by.) 校园网 This one 网关 to process)

This is a little difficult for people who are new to the Internet to understand the difference between intranet IP and public IP, so let's take an example

Let's put 酒店的201房比作内网ip， so 凡是酒店都可能有201房， If you're hungry, yes 服务员说 "I'm in room 201, please bring some food." And if you order takeout, you're right 店家仅说送来201房间 (Intranet IP), it is impossible for people outside to know, so you have to tell the store 某某市某某区某某酒店（公网ip)再加上201房店家才能找到你。 - 运营商 The assigned public network ip Address ( 某某市某某区某某酒店 That is, the hotel where you stayed, and 201房（内网ip） Yes 酒店管家（路由器）所分配的 。 So 一个酒店可以有很多的房间（内网ip） But when a friend outside asks you where you live, you certainly won't say 你住在201房间（内网ip） And will say that you live in 某某市某某区某某酒店（公网ip)。 This is the essential difference between private IP addresses and public IP addresses. 一个对内，一个对外

Attention

1. Public IP address

世界范围的唯一性

, while the intranet IP is only in

局域网内部具有唯一性

2. The intranet IP of all computers in a LAN is:

互不相同的,

but

共用一个外网IP

。

Just like the previous hotel example: your school 校名 There's only one in the whole world, but it's inside your school A栋大楼3层3号教室 It's only unique within your campus. Other schools have them too A栋大楼3层3号教室 。 You can only say to the courier brother please help me deliver the package to xx university, but you can't say please help me deliver the package to classroom 3 on the 3rd floor of Building A.

3. In the local area network, each computer can assign its own IP, but this

IP只在局域网中有效

。 And if you connect your computer to the internet, yours

网络提供商的服务器会为你分配一个IP地址

This IP address is what you are in

外网的IP

。 Two IPs exist at the same time, one internally and one externally.

4. IP on the Internet (

即外网IP

The address is unified by one called

“IANA(互联网网络号分配机构)”

organization to manage. Due to the unreasonable allocation and the limitations of the IPv4 protocol itself, the IP address resources of the Internet are becoming more and more strained.

IANA将A、B、C类IP地址的一部分保留下来，留作局域网使用。

The details are as follows

IP address space:

a类网              10.0.0.0 ~ 10.255.255.255                  b类网              172.16.0.0 ~ 172.31.255.255                  c类网              192.168.0. 0~ 192.168.255.255

In other words, if the IP address you find is within the range of the above A, B, and C IP addresses, it must be the IP address of the local area network, otherwise it is the address of the public network.

5. In real life, there are not only first-level NET technology, but also second-level NET technology. That is, it is possible that your campus gateway is just a local area network. More addresses can be obtained through multi-level conversion.

1. Empirical method

1. General telecommunications

ADSL

The bandwidth is not being upgraded

大带宽

The former is a (dynamic) public IP address. If it costs very little money to upgrade you

100M光纤上网

, 99.99% is an intranet IP, and the 0.01% is that I haven't found a case yet.

2. 99.99% of the agency network operators are

内网IP，如长城带宽、聚友E家等。

3. 99.99% of optical fiber Internet access is intranet IP.

2. Intuitive method

The addresses in the following CIDR blocks are private IP addresses

10.0.0.0 到 10.255.255.255172.16.0.0 到172.31.255.255192.168.0.0 到192.168.255.255

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An IT veteran in the IT industry for nearly two decades. Perennial lurking in state-owned enterprises, each of the first and second tier of large factories. Hardware integration into the industry, all the way to virtualization and containerization. He has worked in system integration, DBA, full-stack development, sre, project manager, product manager, and department director.
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